Variable pitch propeller



June 10, 1941. o. J. HUMPHREJY I VARIABLE PITCH 'PROPELLER Filed July 26, 1939 071mm Jflimphzy,

INVENTOR ATTOR N EY WITNESS:

Patented June 10, 1941 UNITED" STATES PATENT- OFFICE VARIABLE PITCH PROPELLEB Orson J. Humphrey, deceased, late of Elyria, Ohio, by Mary E. Humphrey, administratrlx, Elyria, Ohio Application July 26, 1939, Serial No. 286,700

7 Claims.

This invention relates to variable pitch propellers for aeroplanes.

An important object of this invention is to provide a variable pitch propeller having means under the direct control of the pilot whereby the pitch of the blades may be varied to suit different fllying conditions and speeds of flight of the aerop ane.

Another object of this invention is to provide a propeller of the. above-mentioned character wherein the blades may be djusted radially with respect to the hub of the propeller to increase or decrease the latter's pulling. power.

With these and other objects in view this invention consists in certain novel features of construction, combination and arrangement of parts to be hereinafter more fully described and claimed.

For a complete understanding of this invention, reference is to be had to the following description and accompanying drawing, in which Figure 1 is a side elevation, partly in section, illustrating a device embodying this invention and associated with a fragmentary portion of an aeroplane.

Figure 2 is a vertical sectional view taken on the line 2-2 of Figure l,

Figure 3 is a fragmentary front elevation illustrating the hub of the propeller, and

Figure 4 is a transverse sectional view taken on the lined-4 of Figure 1. f

In the drawing, wherein for the purpose of i1- lustration, is shown a preferred'embodiment of this invention, the numeral l indicates a fragmentary forward portion of the fuselage of an aeroplane wherein the propeller shaft is indicated by the numeral 2 and to which this invention is applied.

A propeller hub 3 is keyed, or otherwise secured, to the shaft 2 and consists of a box-like middle portion 4 having a removable cover and longitudinal sleeve-like extensions 5 to rotatably and slidably receive shafts t formed integrally with propeller blades 1. The shafts 6 are provided with spiral grooves l which receive pins 9 carried by the extensions 5 for the purpose of turning the blades I to vary the pitch during movement of the blades towards and from the hub. The shafts 8 are provided adjacent the blades 1 with grooved portions II engaged by the forked ends ll of shifting members l2. The members I2 are slidabiy supported by the extensions I and enter the box-like portion 4. The portions of the members l2 within the box-like portion "are provided with rack teeth II which mesh with segmental gears ll, pivoted as shown at IS. The segmental gears H are formed with depending arms I, and the links I! are pivoted thereto and to a grooved collar ll splined to the propeller shaft 2. The grooved collar II is engaged by a forked element ll secured to an operating rod 20. The operating rod, which is journaled at one end in the element is, extends through the forward fuselage of the aeroplane to the cockpit and has a hand wheel 2| secured thereto. The rod is screw-threaded, as at 22, which threads mesh with the female threads of a supporting sleeve 22. The hand wheel 2| is located-adjacent the pilot so that the rod maybe rotated in either direction for the purpose of causing the same to move endwise in either direction to impart corresponding movement to the collar is. The movement of the collar II on the shaft 2 will act through the segmental gears ll, operating bars l2, and grooves l and pins 8 to vary the pitch of the propeller blades and adjust the propeller blades towards and from the hub 3.

Thus it will be seen that the pilot can easily vary the pitch of the blades as well as the pulling power of the blades and that the operating means for the propeller blades is simple and compact and will to a large extent be protected against weather elements.

Having shown and described the preferred embodiment of this invention, it will be understood that minor changes in construction, combination and arrangement of parts may be made without departing from the spirit and scope of this in vention.

Having thus described the invention, what is claimed is:

1. A variable pitch propeller comprising a hub including a box-like portion provided with radially arranged sleeve-like extensions, propeller blades having shanks rotatably and slidably received by said extensions, said shanks having spiral grooves, pins secured to the extensions and extending into the grooves to vary the pitch of the blades by the movement of the shafts inwardly and outwardly relative to said extensions and with rotary movement in opposite directions, rack bars slidabiy secured to the extensions and rotatably engaging the shafts and extendin'gihto the box-like portion, segmental-shaped racks meshing with the rack bars and pivotally mounted in the box-like portion,

a member slidably mounted on the propeller shaft and operatlvely connected to move said racks, and manual means the said member.

for slidably actuating 2. A variable pitch propeller comprising a hub including a box-like portion provided with a aaeacei being formed with radial sleeves having inwardly extending pins at the ends thereof; propeller blades having longitudinal shanks slidably and rotatably mounted within said sleeves, said shanks having cam surfaces engaging the pins of the sleeves; actuating means cooperative with bars slidably secured to the extensions and rotatably engaging the shafts and extending into the box-like portion, segmental shaped racks meshing with the rack bars and pivotally mounted in the box-like portion, and means to actuate the said racks from a place remote therefrom.

3. In combination with a driving shaft; a casing rigidly attached to the shaft, said casing being formed with radial sleeves having inwardly extending pins at the ends thereof; propeller blades having longitudinal shanks slidably and rotatably mounted within said sleeves,- said shankshaving cam surfaces engaging the pins of the sleeves; racks having a rotatable connection with the shanks and cooperative therewith to move the same longitudinally within said sleeves in a manner to cause the pins to ride against the cam surfaces to simultaneously axially actuate the said blades; and manually actuated gear means meshing with the said racks in a manner to move the same longitudinally.

4. In combination with a driving shaft; a casing rigidly attached to the shaft, said casing being formed with radial sleeves having inwardly extending pins at the ends thereof; propeller blades having longitudinal shanks slidably and rotatably mounted within said sleeves, said shanks having cam surfaces engaging the pins of the sleeves; pairs .of mutually cooperative gear means mounted within the casing, one of the gear means of each pair having a rotatable connection with the shanks of the said propeller blades, and the other gear means of each pair coacting with the first-mentioned gear means to move the shanks longitudinally within said sleeves. in a manner to cause the pins to ride against the cam surfaces to simultaneously axially actuate the said blades; and means cooperative with the second-mentioned gear means to actuate the same from a point remote therefrom.

5. In combination with a driving shaft; a cas ing rigidly attached to the shaft, said casing the said propeller blades to move the same lon itudinally within said sleeves and to cause the pins to ride against the cam surfaces to simultaneously axially actuate the said blades, said actuatingmeans including rack bars connected to the said propeller blades and slidably mounted within the casing and segmental gears pivoted to the casing in meshing relation with the said racks.

6. In combination with a driving shaft, a casing rigidly attached to the shaft, said casing being formed with radial sleeves having inwardly extending pins at the ends thereof; propeller blades having longitudinal shanks slidably and rotatably mounted within said sleeves, said shanks having cam surfaces engaging the pins of the sleeves; actuatingmeans cooperative with within. the casing and segmental gears pivoted tothe casing in meshing relation with the said racks; and link means pivoted tothe segmental gears .to actuate the same from a place remote therefrom.

"I. In combination with a driving shaft; a casing rigidly attached to t e shaft, said casing being formed with radial eeves having inwardly extending pins at the ends thereof; propeller blades having longitudinal shanks slidably and rotatably mounted within said sleeves, said shanks having helical grooves receiving the pins of the sleeves; and actuating means cooperative with the propeller blades to move the same longitu'dinally within said sleeves and toxcause the pins to move within the helical grooves to simultaneously effect the axial actuation of the said propeller blades, said actuating means including a rack bar connected to the said propellers and slidably, mounted within the casing and segmental gears pivoted to the casing in meshing relation with the said racks.

- MARY E. HUMPHREY,

Administratria: of the Estate of Orson J. Humphrey, Deceased. 

